Abstract :
Quantum computing is a rapidly evolving field with the potential to revolutionize information processing. Spins in semiconducting materials hold great promise for large-scale quantum computing due to their compactness and compatibility with standard CMOS processes. However, scaling spin-based quantum processors presents a key challenge: maintaining qubit fidelity as the system size increases. In state-of-the-art devices, heating effects, primarily caused by dissipation from control pulses, have emerged as a limiting factor. Notably, systematic drifts in the Larmor frequency of spins have been observed following microwave excitations, revealing a complex temperature dependence whose origin remains elusive.
This thesis focuses on hole spins in silicon MOS devices. Leveraging the strong spin-orbit coupling experienced by these particles, we explore the thermal susceptibility of hole spins, unveiling a possible electric origin of this effect. As the thermal susceptibility renders spin qubits highly sensitive to heating, we develop local microsecond thermometry to quantify dissipation associated to quantum operations. Additionally we examine the longitudinal interaction with a quantized field that has promising implications for large scale connectivity and readout of spin based processors. Driven by an fondamental interest in the properties and interactions of hole spins with their environment, this thesis might provide valuable insight for developing scalable, robust quantum processors.